correct way to setup cool tube venting?

[JonnneyB]

setup: 38"X38"X78" grow tent with 6" cool tube with 400watt lamps.
I was gonna put carbon filter to cool tube to 4" inline fan to outside vent on top.. On bottom 4" inline fan pushing in room air.. This seemed to be the easiest way.. but last nite while reading threads here..smoking mom was on a thread saying not to put scrubber onto cool tube but to run it by it`s self and then have another for the filter. This makes sense but would be a lot more work...
So I am wondering if the first way will work or should I run two seperate vents? And if I need to run two vents can I tee or y them to the single outside vent? Also if the 4" inline fan with 90 cfm isn`t enough to cool lite I have a 4" can fan with 170cfm to swap out...all help and comments accepted with thanks.

 

[The Hemp Goddess]

setup: 38"X38"X78" grow tent with 6" cool tube with 400watt lamps.
I was gonna put carbon filter to cool tube to 4" inline fan to outside vent on top.. On bottom 4" inline fan pushing in room air.. This seemed to be the easiest way.. but last nite while reading threads here..smoking mom was on a thread saying not to put scrubber onto cool tube but to run it by it`s self and then have another for the filter. This makes sense but would be a lot more work...
So I am wondering if the first way will work or should I run two seperate vents? And if I need to run two vents can I tee or y them to the single outside vent? Also if the 4" inline fan with 90 cfm isn`t enough to cool lite I have a 4" can fan with 170cfm to swap out...all help and comments accepted with thanks.

SmokinMom was right! Run 2 separate vents. I wouldn't recommend teeing or wying them together. If you tee/wye them together, you are going to have to go to a 6" line and you will have to install baffles on the outgoing 4" lines so that the air does not flow backward. To my way of thinking, it would be far easier to run another 4" exhaust out.

Use the 90cfm for the light and the 170cfm for the filter.

 

[ugmjfarmer]

I am running a cool-tube from Hydrofarm with a HTG-Supply 6" Inline fan and a HTG 6" Carbon Filter (combo was $179 or something). Works great with the air going from filter to cooltube to fan to roof vent.

This time of year I have the fan speed at the lowest possible and my temps are still 73 degrees at the light, but in the summer with full speed i can maintain 73 as well (as long as the ambient air in the house is that low).

 

[ugmjfarmer]

I should add though, my cabinet is much smaller. Its a closet next to a wet wall, so there is exposure to the outdoors. YMMV, my cab sits at 63 degrees today for a low temp.